As we notice download is more error prone when there is a download surge. The download center’s package success rate grows much lower as the package size grows bigger. This imposes the big challenge for downloading big VS SKUs. I think we should look into the P2P content distribution technology Avalanche.
Avalanche is a research project that provides faster and more cost effective distribution of data files to large user populations (e.g. software download such as Express, VS products, software updates etc.) This is achieved by allowing clients simultaneously obtain different pieces of files from multiple nodes on internet than just MS download center servers. Avalanche uses a similar architecture but with an improved protocol that removes some limitations of the BitTorrent protocol.
Avalanche is expected of the following
1. Avalanche is more resilient to peer leaving the network: Avalanche combines chunks (like a XOR) before sending them, you don’t need to have a specific chunk A, you only need enough combination that you can extract chunk A out
2. Avalanche imposes less load on the servers: BitTorrent servers needs to track which clients have chunk A, but Avalanche doesn’t.
3. Avalanche added feature for security reasons. It restricts to only distribute MS signed package
4. Avalanche could provide about 2-3 times faster downloads than BitTorrent and about half the server requirements (Based on http://www.pam2004.org/papers/148.pdf, BitTorrent was used to distribute the Linux RedHat 9 ISO (1.77 GB) to more than 180,000 clients (over 5 months) using two servers with not super high end links (I have heard 5Mbps, needs to be confirmed).
Pablo Rodriguez Rodriguez and Julien Couvreur have done great work for describing the technologies in details in their URL at http://blog.monstuff.com/archives/000201.html http://research.microsoft.com/~pablo/avalanche.htm and